Heat sensitive suspended ceiling structure



April 19, 1966 w. s. YouNG, JR 3,246,432

HEAT SENSITIVE SUSPENDED CEILING STRUCTURE Filed OC'. 26, 1962 IN VENTOR.'

I/I/ E. B/ZIUNG.

ATTYB.

United States Patent Y 3,246,432 HEAT SENSITIVE SUSPENDED CEILING STRUCTURE Walter S. Young, Jr., Darien, Conn., `assignor toOwenslCorning Fiberglas Corporation, a corporation 'of Delaware f Filed 0ct.26, 1962, Ser. No. 233,376

2 Claims. (Cl. 52-98) This invention relates to improvements in construction 'of virtual 'or false'ceilings and'th'e'like, and is particularly directed 'to heat softenable support elements for use in such construction.

Falsevceilings` generally comprise a plurality of grid bar units adapted to, be `hung in areas beneath an upper floor ori overlying root' in a room or building area and which are adapted to receive rectangular panjels of -prefabricated. materials/suchas fibrous glassV tiles, gypsum board, plywood. orfmetal pans or the like.l These-ceilings usually are suspended by use of wires, hanger rods or other means, aixed to the underside of the 'roof or floor .thereabove in a manner-to present a neat, level and decorative appearance in the room therebelow.

Usually such ceilings, aside from being solely decorative, arel utilized to provide fmeans of concealment of auxiliary *building equipment such as power lines, air duets, service piping, etc., as well as to con-ceal rough `or unfinished kparts of wallsvor ceilings of a building. Furthermore,heat sensitive sprinklers or other tire protective devices inay be included with such equipment and likewise may be concealed substantially if not completely by such ceilings; however the sprinkler heads 'or nozzles associated with such devices ordinarily are required to be exposedto view below such a ceiling in order to be of desired 'effect during a tire.

One of the objects of the present invention is to provideal simple, eifective, economic, heat sensitive and decorative ceiling structure having the lutilitarian quality of permitting con-cealment ofiire nozzles and other tire protective devices associated therewith behind such a decorativeceiling while also' preserving thefeficacy ofthe fire protective devices.k 4- v.Another object is to provide `a heat softenable support means for a ceiling panel element comprised in this invention.

'-Another object-is to provide a heat sensitive ceiling construction which will `give way or collapse, or drop out at least in part when an abnormal or otherwise undesirable increase in temperature occurs adjacent the ceiling structure, thereby exposing vthe previously concealed protective devices and expediting their intended u-se.

The invention as herein described comprises a suspended ceiling structure having vertical rods or wires aiiixed to the underside of an upper lioor or roof adapted to suspend the ceiling at a predetermined elevation therebelow. Suitable horizontally disposed grid. bars are arrangedto form acellular skeleton framework for the structure and are adapted to support a plurality of rectangular ceiling panels arranged in predetermined patterns, the grid'bars being formed or otherwise provided 'with narrow lledges or ange elements extending horizontally from the vbody or web of each of the bars in a manner to offer support -for the edges of uthe panels placed thereon. T he ledges or iiange elements are formed of a heat soltenable material-'such as for'example a synthetic thermoplastic resin which will deform characteristically when subjected to relatively high ambient temperatures to permit collapse of the supporting flanges and subsequent fall out or drop out of the panels comprising the ceiling structure, the previously concealed protective devices being exposed thereby to the high ambient temperature to permit procedural functioning thereof.

3,245,432 Patented Apr. i9, 1965 The above mentioned and `other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 illustrates in cross section a conventional manner in which a ceiling panel may be suspended below an upper floor by use of grid bars and lwire hangers together with certain heat softenable support elements comprising this invention;

FIGURE 2 illustrates one type of grid -bar comprising a heat softenable-material and adapted ordinarily to support ceiling tiles or panels in a conventional manner;

FiGURE 3 illustrates another type of grid bar-similar to that of FIGURE 2, out with certain modified structural characteristics adapted to induce faster collapse of the ceiling; V

FIGURES 4 and 5 illustrate how a combination of metal and heat softenable resin may rbejoined together g to form a-uni-tary ceiling panel support bar; and

FIGURE 6 illustrates a modified type of construction comprising a heat softenable ceiling panel support element adapted for attachment to a conventional metal grid bar. Withrefere nce.now to FIGURE l, a false ceiling 1t) may besuspended from the underside 11 of a tioor or roof member 12 in a conventional manner by means of hanger rods or wires 14, cleats 16, and a plurality of grid bars 18 having -substantially permanent support therefrom such as for example, hook and eye connection 2t) with the rods 14. The ceiling structure 10 comprisesrectangular panel elements or tiles 22 adapted to rest on thermosensitive anges 24 extending horizontally from and along the grid bars 18, and forms an enclosed space 26 with the roof member 12 thereabove. The ducts 2S adapted to convey air, water, wiring, power lines, etc., may be completely concealed in the space 26 above the ceiling. Fire protective' device-s such as for example, a sprinkler lsupply pipe 30 having thermosensitive sprinkler heads 32 associated therewith also may be concealed in the space 26 in order to more effectively preserve the decorative quality of the ceiling 10.

The effectiveness of the sprinklers when so concealed is maintained by means described herein as follows: the grid bars 18 and thermosensitive anges 24 associated therewith may be formedof a material such as a thermoplastic resin having the characteristics and properties of deforming sufficiently when heated to a predetermined temperature to permit drop out of the ceiling panels 22 and also to permit subsequent exposure oi the thermosensitive sprinkler heads 32 to thenewly elevated temperatur'e `thus enabling the protective devices 30, 32 to function in their respective manner.

As may be seen in FIGURE 2, one form of grid bar 18 may comprise a vertical web member 34 having spaced apart eyelets or lopenings 36,a=dapted to receive the hanger wires 14 for support thereof. The flanges or ledges -24 extend vsidewarlly from the web 34 in a normally rigid form to support ,the ceiling pane-ls 22 thereon. The ledges 24 may be VVof predetermined thickness and sufficiently heat sensitive as `to become limp when subjected to increased ambient` temperatures, an-d collapse o-r sag or otherwise deform to a position 24a, thus enabling the tile or panel member 22 to drop out or fall away from its normal position inthe ceiling and expose the protective devices thereabove 'to the increased ambient temperature.

Another form vof grid bar 18' may be seen in FIGURE 3 to comprise a web member 34 hav-ing eyelet openings 36 and flange members 24 adapted to deform under the influence of a change in temperature to a position 24a. This form comprises in addition, a central linear co-re or zone 38 of reduced thickness along the juncture Y 3i of the lflanges 24' and web 34. This zone of reduced thickness may comprise longitudinal grooves 39 extend-jing along the zone 38 in order to provide a greater degree of heat sensitivity at a predetermined and restricted portion of the grid bar and thus permit a more rapid collapse of the ceiling structure. i

In FIGURES 4, 5, and 6 there is disclosed a type of grid bar construction wherein the provision of a main supporting bar or web element of metal supplies a greater degree of rigidity and firmness to a ceiling support structure than when construction is restricted solely to the use of thermoplastic materials per se.

With particular reference to FIGURE 4, there is indicated a main =reinforcing bar 40 of metal or other heat resistant material and having eyelets 42 welded or otherwise affixed to the bar 40 for use in hanging or suspending the ceiling in a conventional manner. Lateral openings 44 may be pro-vided in the ordinarily vertically disposed web portion 46 yof the bar for the purpose of anchoring a thermosensitive element 48 thereto. The thermosensitive element 48 may be molded or extruded or otherwise attached or bonded to the bar and may be provided with horizontally disposed flange portions 50 extending longitudinally along the lower edge of the web to provide support means for a ceiling tile which may be installed thereon. The thermosensitive material may substantially surround the web portion 46 of the bar as it envelops the opposite faces thereof, the material preferably also passing laterally through the openings 44 to assist in permanently atiixing the thermosensitive material to the bar. The flanges 50 while extending normally outwardly horizont-ally from the web portion 46 will be caused to droop or sag under the influence of a rise in ambient temperature and will assume a substantially downwardly disposed position 50a thereby.

Another type of construction as disclosed in FIGURE o may comprise a metal bar 60 having eyelet openings 62 therein to provide fastening means `for a plurality of conventional hanger rods or wires or the like, and heat sensitive flange members 64 adapted to support ceiling panels or tiles which may be installed thereon and to be normally supported thereby. This particular construction comprises spaced openings 66 in the web 60, adapted to receive a plurality of rivets or pins 68 extending therethrough. Lips 7i) projecting 'upwardly from the juncture of the anges 64 and extending longitudinally therewith may be provided with correspondingly spaced openings 66 also adapted to receivethe pins 68 and thereby secure the anges 64 to the bar 60. As the flanges 64 become heated under the inuence of -an increased ambient temperature they will sag or collapse to a depending position 64a and thus permit drop out of the ceiling tile normally supported thereby.

In FIGURE 6 there is disclosed a type of grid bar 72 having eyelet openings 74 adapted to receive conventional hanger rods or Wires (not shown) and having formed at the bottom edge thereof laterally disposed ange portions 76 adapted to receive and support thereon ra pair of thermosensitive transverse Iledge or Vilange members or elements 78 running longitudinally and contiguously along the flange portions 76 on the bar 72 to provide thermosensitive support means for ceiling tiles or panels which may be installed thereon. The ledge members 7,8 .may be formed as a unitary structure having a common central juncture or zone 80. 4

Projecting upwardly land inwardly from the thermosensitive ledge members 78, and immediately adjacent the flange members 76 onrthe bar72 there may be provided a pair of mating and opposed hook shaped ribs 82 yadapted 't0 reach upwardly and inwardly over the flange ymembers 76 to provide la firm support for the ledge members 78, and the ceiling tiles whichmay be installed thereon.

When the heat sensitive ledge members 78 are subjected to an increased ambient tempera-ture such as in case of re, the ledge members characteristically will become limp rand will sag to a generally downwardly extending position 78a and permit collapse or drop out of the ceiling panels mounted thereon. y

In systems where lighting panels are supported b'yfV the grid or where novel decorative variatio-ns in the supporting structure `are desired, the grid bars or the supporting ledge portions of such bars can be of transparent or translucent material as desired. Such light transmitting materials incorporated in the grid bars, besides providing a wider range offdecorative effects, can be util-ized to minimize the visibility of the supporting 'elements by making them relatively transparent, or vcan be utilized to permit ad-dition-al transmission of light therethrough when incorporated in a lighting system.

While there is described above the principles of this invention in co-nnection with specic apparatus, it is to be clearly understood that this description is made only by way of example yand not as a limitation to the scope of this invention. l

I claim:

1. A grid bar for a suspended ceiling construction in which removable panels are supported by a plurality of said bars, said grid bar comprising a generally rigid thermally resistant upstanding web portion adapted for suspension from an overlying support structure and being aligned in a ceiling position, and a thermally responsive longitudinal ange portion continuously connected to said web portion and extending laterally therefrom along its length, said thermally responsive iiange being adapted to support an edge of a ceiling panel under conditions of a predetermined thermal range and to deform and release the support of said panel edge vunder conditions of ternperature above said thermal range, said thermally responsive ange having a linear zone of reduced thickness extending along its length at which thev deformation of said ilange occurs to release a supported panel edge at temperatures above said thermal range.

2. A grid bar for a suspended ceiling construction in which removable panels are supported by a plurality of said bars, said grid bar comprising a generally rigid thermally resistant upstanding web portion adapted for' suspension from an overlying support structure and being aligned in a ceiling position, and a thermally responsive longitudinal flange portion continuously lconnected to said web portion and extending laterally therefrom along its length, said thermally responsive ange being adapted to support an edge of a ceiling panel under conditions of a predetermined thermal rangerand to deform and release the support of said panel edge under conditions of temperature above said thermal range, said thermally responsive flange being of different material from that of the upstanding web portion.-

References Cited by the Examiner Findlay j j 5 ,2-47 6 FRANK ABBOTT, Primary Examiner. Y. y i i HENRY C. SUTHERLAND, Examiner, 

1. A GRID BAR FOR A SUSPENDED CEILING CONSTRUCTION IN WHICH REMOVABLE PANELS ARE SUPPORTED BY A PLURALITY OF SAID BARS, SAID GRID BAR COMPRISING A GENERALLY RIGID THERMALLY RESISTANT UPSTANDING WEB PORTION ADAPTED FOR SUSPENSION FROM AN OVERLYING SUPPORT STRUCTURE AND BEING ALIGNED IN A CEILING POSITION, AND A THERMALLY RESPONSIVE LONGITUDINAL FLANGE PORTION CONTINUOUSLY CONNECTED TO SAID WEB PORTION AND EXTENDING LATERALLY THEREFROM ALONG ITS LENGTH, SAID THERMALLY RESPONSIVE FLANGE BEING ADAPTED TO SUPPORT AN EDGE OF A CEILING PANEL UNDER CONDITIONS OF A 